I wonder if the fact that it's above your head makes a difference - people =
are generally better at localisation in azimuth horizontally than at altitu=
de=85
--Leslie Smith
On 25 Jun 2013, at 09:46, Jennifer M. Groh wrote:
> Dear List,
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> I am writing a book for a general audience on how the brain processes spa=
tial information ("Making Space"). The chapter on hearing covers many topic=
s in sound localization, but there is one that I'm currently still quite pu=
zzled about: why it is so hard to localize a smoke detector when its batter=
y starts to fail? Here is what I have considered so far:
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> - To my ear, the chirp sounds high frequency enough that ILD cues should =
be reasonably large.
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> - At the same time, it seems to have a broad enough bandwidth, and in any=
case it has onset-and-offset cues, that ITD cues should be usable.
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> - A possibility is that the chirp is too brief, and that limits dynamic f=
eedback, i.e. changes in ITD and ILD as the head turns during a sound. Ho=
wever, in my laboratory we have obtained excellent sound localization perfo=
rmance in head-restrained monkeys and human subjects localizing sounds that=
are briefer than the reaction time to make an orienting movement.
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> - An additional possibility is that we have too little experience with su=
ch sounds to have assembled a mental template of the spectrum at the source=
, so that spectral cues are of less use than is normally the case.
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> I'm leaning towards a combination of the last two factors, which together=
would render the cone of confusion unresolved for these stimuli.
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> Thoughts?
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> Best wishes,
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> --Jennifer Groh
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> --=20
> Jennifer M. Groh, Ph.D.
>=20
> Professor
> Department of Psychology and Neuroscience
> Department of Neurobiology
> Center for Cognitive Neuroscience
>=20
>=20
> B203 LSRC, Box 90999
> Durham, NC 27708
>=20
> 919-681-6536
> www.duke.edu/~jmgroh
Professor Leslie S. Smith B.Sc. Ph.D. SMIEEE,
Head, Institute of Computing Science and Mathematics, School of Natural Sci=
ences
University of Stirling,
Stirling FK9 4LA, Scotland
l.s.smith@xxxxxxxx=20=20
Tel (44) 1786 467435 Fax (44) 1786 464551
www http://www.cs.stir.ac.uk/~lss/
--=20
The University of Stirling is ranked in the top 50 in the world in The Time=
s Higher Education 100 Under 50 table, which ranks the world's best 100 uni=
versities under 50 years old.
The University of Stirling is a charity registered in Scotland,=20
number SC 011159.